molecular formula

50mL hydrocarbon having 85.7% Carbon at STP on combustio ngives0.37 g CO2 ,0.142g of H2O and unknown qty. of methane.Determine molecular formula of hydrocarbon

1 Answers

1357
Manish Shankar ·

% of carbon=85.7%
% fo hydrogen=14.3%
85.7/12=7.14
ratio of C:H is 1:2

so the hydrocarbon is (CH2)n

let the moles of hydrocarbon be x, then x=PV/RT

Let the moles of methane be y

applying POAC on C and H we get

nx=.37/44 + y
2nx=2*0.142/18 + 4y

find n and then molecular mass

Your Answer

Close [X]